Map of the Byzantine Empire 668 AD

The previous century has been traumatic for the Byzantium. The Empire's borders to the north, along the Alps and the River Danube, were placed under pressure in the late 6th Century, and finally breached by a succession of barbarian invasions from Lombards, Avars, and Slavs. Meanwhile in the east a catastrophic, though ultimately victorious struggle with the Persian Empire had been surmounted by the sudden eruption of Islam from the Arabian Peninsula.

For a number of reasons, still debated - religious and political alienation of local populations, economic and military exhaustion, failure of strategic oversight - the Byzantine government is unable to prevent the loss of Egypt, Palestine and Syria. The newly established Umayyad Caliphate, with its capital in Damascus, places continuous pressure upon Byzantium, which withdraws behind the Taurus mountains and consolidates what is left of its military in Asia Minor.